Help,should I ask her?

I have been talking to a girl for a while now. About a couple of weeks ago I asked her if she had a boyfriend and she said no. Well, some time have passed since that. Today a guy posted on her fb wall talking about how he loves her and he is glad to have met her, she is my love, etc. etc. Of course with me liking her I have become very worried. She ignored the post but still. I checkedhis fb page and his relationship status recently changed to in a relationship. He also mentioned her as his wifey. Well, should I ask her if they are together or would that make me look like a jealous stalker or something? It's killing me because she told me she liked me and we were going to hang out soon so this confused me. She was texting me a bunch today and she didn't mention anything. Should I ask her?